It's part of the reason why federal officials are rescinding the 2011 policy that allowed national parks to ban the sale of bottled water in an effort to curb litter.

It wasn't as effective as officials had originally hoped. While most parks with concession stands discontinued the sale of bottled water, they still allowed sales of bottled sweetened drinks.

"The 2011 policy was intended to reduce the amount of plastic that enters the waste stream at a park and to promote recycling and education about disposable plastic water bottles," the National Park Service officials said in a statement. "It was ultimately determined that there are more effective ways to promote recycling and reduce litter while still providing as many safe, healthy hydration options as possible to our visitors."

Twenty-three of the 417 national parks decided to stop selling disposable water bottles once the policy was enacted in 2011, including Saguaro National Park in southern Arizona.

"It's probably to make money, so people buy bottles and there's a mark-up on them so the concessions make money," Kozan said about the decision to allow water bottle sales once again.

His theory might not be too far-fetched.

According to an Associated Press report, the bottled water and beverage industry has lobbied aggressively to keep single-use bottled water in the national parks.

International Bottled Water Association spokeswoman Jill Culora praised the National Park Service's decision in a statement, calling the policy "seriously flawed" and noted it still allowed other less healthy beverages that are packaged in heavier types of containers, the report said.

Studies have shown that plastic bottles are one of the biggest sources of pollution in places like the Grand Canyon, the AP report stated. In a 2012 report by the National Parks Service, the Grand Canyon found large decreases in bottles found on trails, and cited birds and other animals getting plastic chunks of bottle lodged in their throats.

Some visitors think the ban has been effective.

"It was remarkably clean because I've seen a lot of other smaller parks where I've seen a lot of litter, actually. I was quite pleased to see that it's pretty clean," said Kevin Leong, from Singapore, who drove the Saguaro National Park East loop.

Saguaro National Park sells refillable water bottles in its visitor center, for those people who don't bring their own. They have a bottle refilling station right outside the front door.

There is no plan to remove those water stations.

Saguaro National Park East does not have a concession stand, nor do they have a vending machine that sells sugary drinks.

"We will continue to encourage the use of free water bottle filling stations as appropriate, but ultimately it should be up to our visitors to decide how best to keep themselves and their families hydrated during a visit to a national park," according to the statement from the National Park Service.

Effective immediately, concession providers will now be allowed to sell single-use water bottles, if they so choose, in coordination with park management.

But visitors like Leong don't want the trails to suffer the consequences.

"I'd like to hope that people would pick their bottles and bring them home to trash them, rather than throw them in the desert," he said.

Dozens of people spent Wednesday afternoon putting the finishing touches on their wagons for the annual Tucson Rodeo Parade. There are a total of 81 wagons in this year's parade. Close to 2,400 people and 560 horses will be walking in the parade as well.

Dozens of people spent Wednesday afternoon putting the finishing touches on their wagons for the annual Tucson Rodeo Parade. There are a total of 81 wagons in this year's parade. Close to 2,400 people and 560 horses will be walking in the parade as well.